Index: libcxxabi/trunk/CMakeLists.txt
===================================================================
--- libcxxabi/trunk/CMakeLists.txt
+++ libcxxabi/trunk/CMakeLists.txt
@@ -70,6 +70,10 @@
   set(PACKAGE_STRING "${PACKAGE_NAME} ${PACKAGE_VERSION}")
   set(PACKAGE_BUGREPORT "llvm-bugs@lists.llvm.org")
 
+  if (NOT DEFINED LLVM_INCLUDE_TESTS)
+    set(LLVM_INCLUDE_TESTS ON)
+  endif()
+
   if(EXISTS ${LLVM_MAIN_SRC_DIR}/utils/lit/lit.py)
     set(LLVM_LIT ${LLVM_MAIN_SRC_DIR}/utils/lit/lit.py)
   else()